The Perils of Excessive Water Use in Cities

Featured

24th August 2018

News earlier this year brought the issue of water conservation and the potential perils of uncontrolled city water usage to the attention of the world.

Cape Town in South Africa is at crisis point. The city is in the midst of a three-year drought that has led to severe water rationing, with a limit of 13 gallons (50 litres) of water usage allowed per person, per day. Although severe rationing has helped the situation, there is still a critical water shortage.

‘Day Zero’, the point when at least a million homes in Cape Town will be without running water, was originally scheduled for April this year. Thankfully, with dam levels rising in the rest of the country, this has now been pushed back to 2019. However, the 50-litre water restrictions remain in effect, with dam levels for the Western Cape Province, which includes Cape Town, still at just 18.3 percent.

The global risk

While we might like to think the situation in Cape Town is the result of a freak, once-in-a-century drought, unfortunately, that’s just not the case. Sao Paolo in Brazil, a megacity with some 20 million residents, faced its own Day Zero in 2015. The city was forced to turn off the water supply for 12 hours a day, resulting in the closure of businesses and the failure of entire industries.

There have also been serious water shortages much closer to home. In 2008, Barcelona was forced to import tankers of freshwater from France. And with droughts becoming more frequent and severe, serious water shortages are becoming common around the world. In fact, 14 of the world’s 20 megacities are now experiencing water scarcity as a result of drought.

The situation in London

Here in the UK, we are famed for our changeable climate, but even we’re not free from potential water scarcity. In fact, our own megacity of London is facing water demand that is expected to exceed supply within the next decade, and there could be severe shortages in the capital by 2040.

Despite the high rainfall associated with the UK, the metropolitan area actually receives less rainfall (at around 600mm each year) than cities like Istanbul and Sydney. This relatively low rainfall combined with a growing population and hotter, drier summers, could be a recipe for disaster. In fact, in order for London to avoid extreme water stress, experts say the city needs to cut consumption and make river preservation a priority.

Reducing city water usage

Clearly, the current rate of city water usage needs to change. One of the biggest issues is water leaks, with the current scale of the problem likely to be much bigger than reported. Funding for water systems will have to increase so that money can be spent improving the ageing infrastructure.

Households also need to change their attitudes to water conservation. Low-flow and water-efficient indoor fixtures can be a big part of that change, helping to reduce indoor water use from an average of 50 gallons per person, per day down to a usage rate of between 30 and 35 gallons.

However, for residential users, it’s outside the home where you’ll find the most glaring water waste. Over half of urban water use is outdoors, and since outdoor use is completely discretionary, it’s something we can easily reduce. In fact, even the simple act of washing the car can use up to 300 litres per wash.